Show custom grid or any custom information in magento admin sales order view page

Show custom grid or information in magento admin sales order view page:
Normally, in magento if you open admin – sales order view page, you will get detail above that order. Wiil get the detail of the product in that order. ExK: Which payment gateway is used,billing, shipping address, shipping detail, order amount detail. By the way the same page, you can show your own detail as a block file, we can show like below way.
Step:1
htdocs\app\design\adminhtml\default\jute\template\sales\order\view\tab\info.phtml
In this file, call your model or block or own html table structure.Here am calling my own function like below
echo $this->getShowmydetail();

Step:2
htdocs\app\code\local\Jute\Adminhtml\Block\Sales\Order\View\Tab\Info.php
Override above file from core to your local. Here my local is Jute.
ex: public function getShowmydetail(){ return “hi Hello”;}

Thats it, clear cache and check magento admin – sales – order view page. You will your own detail